Magnetic Electronic Skins For Self-Supervised Origami Soft Actuators

Soft actuators are coming closer to the capabilities of biological mechanical systems.[1] Biomechanics rely on soft, reconfigurable, and efficient structures that allow the
movement, displacement, and interaction of biological systems with their environment. Among others, magnetic soft actuators excel due to the untethered actuation via
electromagnetic fields.[2] Such electromagnetic actuation can be controlled via permanent magnets or coils. Alternating magnetic fields combined with the smart design
of soft actuators have achieved 100 Hz actuation speeds which are attractive to quickly react and adapt to environmental conditions.[3] Additionally, magnetic origami-like
actuators can be specifically magnetized to achieve more complex shape morphing.[4] To close the loop between the actuation of soft systems and the control of their
movements is needed a suitable sensing unit. Robotic systems are normally integrated with sensing awareness to interact with their surroundings. Flexible sensors
mechanically conformal with soft actuators are still under research development. Here, we show the first adaptation of magnetosensitive skins laminated on magnetically
actuated soft actuators.[5] Ultrathin conformal magnetic field GMR and Hall effect sensors were used to detect the magnetization state, the orientation, and the folding
state of origami-like actuators. The magnetic origami foils were made of NdFeB microparticles in PDMS. We found the best thickness and concentration parameters to
achieve untethered magnetic folds defined on the fly. We demonstrate the synergistic combination of magnetic soft actuators and e-skins allowed self-guided assembly into a
box and boat-like layouts. The assembly process was followed and controlled by the signal recovered from the laminated sensing e-skins. We expect further alike integrations for autonomous remote soft mechatronic systems, where untethered actuation is needed.
[1] A. Miriyev, et al. Nat. Commun. 8, 596 (2017)
[2] S. Wu, et al. Multifunct. Mater. 3, 042003 (2020)
2022 IEEE NAP / Abstract 2
[3] X. Wang, et al. Commun. Matter. 1, 67 (2020)
[4] Y. Kim, et al. Nature. 558, 274 (2018)
[5] M. Ha, et al. Adv. Mater. 33, 2008751 (2021)